Double Layer Capacitance

Definition - What does Double Layer Capacitance mean?

Double layer capacitance is a way to store an electrical charge using an electrode, having a double layer, immersed in an electrolyte. These two layers consist of oppositely charged ions. They are insulated by a thin layer that sticks to the electrode's surface.

Double layer capacitance is used quite frequently in the modern era; super capacitors often use double layer capacitance as a means to achieve their high capacities.

Corrosionpedia explains Double Layer Capacitance

Hermann von Helmholtz first discovered the presence of and theorized the double layer in 1879. Many other researchers since then have contributed to the knowledge of the double layer.

The thin layer of ions that contacts the electrode surface and serves as a dielectric is usually less than one hundred nanometers thick.